Bridge plate counterbalance device



Nov. 9, 1965 A. M. BOONE 3,216,373

BRIDGE PLATE COUNTERBALANCE DEVICE Filed Dec. 16, 1963 4 Sheets-Sheet 149 i la [in //6 /324 \j-.[

. I" an "r" I /2 .j "470 v 22 2/ la 23 INVENTOR.

ARTHUR M BOO/V5 Nov. 9, 1965 A. M. BOONE BRIDGE PLATE COUNTERBALANCEDEVICE 4 Sheets-Sheet 2 Filed Dec. 16, 1963 INVENTOR. QARTHUR M BOO/W5Nov. 9, 1965 A. M. BOONE BRIDGE .PLATE COUNTERBALANCE DEVICE 4Sheets-Sheet 5 Filed D90. 16, 1963 INVENTOR.

Nov. 9, 1965 oo 3,216,373

BRIDGE PLATE COUNTERBALANCE DEVICE Filed Dec. 16, 1963 4 Sheets-Sheet 4INVENTOR. A RTHU/P M. BOO/V5 United States Patent Office 3,216,373Patented Nov. 9, 1965 3,216,373 BRIDGE PLATE COUNTERBALANCE DEVICEArthur M. Boone, Michigan City, Ind, assignor to Pullman Incorporated,Chicago, 131., a corporation of Delaware Filed Dec. 16, 1963, Ser. No.330,761 4 Claims. (Cl. 105-458) This invention relates to a new andimproved bridge plate assembly for railway vehicles of the piggybacktype. More specifically, the present invention relates to a new andimproved bridge plate assembly having a simplified but efiicientcounter-balancing device associated therewith, in order to minimize theelfort required to move the bridge plate from a horizontally disposed oroperative position to a substantially vertical or transit position orvice versa.

The popularity of piggyback type hauling has been ever increasing due tothe improved car structures and associated shock dissipating means whichserve to protect the piggyback lading through transit. The individualrailway cars employed in piggyback lading operations are provided withbridge plates to assist in the rapid loading and unloading of thevarious forms of lading by permitting the same to be driven or pulled tothe particular car occupied during transit.

Shock dissipating devices have resulted in the couplers of theassociated cars to be extended up to several feet from the end of thecar in order to accommodate the more popular types of shock dissipatingmeans. Accordingly, the bridge plates on such cars must be increased intotal length in order to span the increased distance between adjacentcars having extended couplers in coupled relationship. As a result, theincreased length of the bridge plate generally requires the centralsection thereof to be increased in vertical depth to resist theanticipated increase in shear forces. Normally, this requires bridgeplates to be heavier and bulkier than predecessor types and thereforerequires considerable effort to move the same between the operative andinoperative positions. As a result, what was once a one man job instoring or lowering bridge plates oftentimes now requires the effort oftwo men.

Loading and unloading of trailers is presently a one man operation sincethe development of the pull-up types of fifth wheel stands and tractorsto cooperate with the same. Obviously, it would be highly desirable itsuitable means could be provided to enable bridge plates to be raisedand lowered by one man without fear of overexertion or injury thereby tomaintain the loading and unloading operation a one man job, with theexpected reflections in the overall cost of piggyback hauling.

The present invention is directed to a simplified and economical answerto the problem set out above. A counterbalance device is provided forready attachment to existing bridge plate designs as Well as beingeasily applied to new models of integrated transportation types ofspecialty cars having extended bridge plates. The present inventionserves to materially reduce the effort required to move the extendedbridge plates between the inoperative and operative positions andpermits easy operation by the efforts of one man.

Broadly speaking, counterbalances have been used in a wide variety ofapplications ranging from double hung windows, draw bridges and the liketo primitive types of lever means to assist in withdrawing water fromlakes and rivers. In the railroad intustry, counterbalance devices havebeen provided on platforms of passenger cars and the like, such devicesusually acting on a spring means in torsion. In the freighttransportation end of the industry, the special sill struture requiredto accommodate the shock dissipating means, eliminates any possibilityof using most of the known prior art types. Other types areautomatically eliminated for other reasons such as inefliciency, or inthe great bulk of the cases, the complex and expensive constructionrequired.

The present counterbalancing device provides a number of advantages inthe form of reduced costs of construction, generally attributable to theoverall minimization of working parts, and is exceedingly simple toinstall on existing cars as well as those currently being manufactured.The placement of the counterbalancing device of the present invention issuch that it will not interfere with the cushioned travel of slidingsills, or the uncoupling mechanisms associated therewith. In addition,maximum eiiiciency will be obtainable to minimize the total effortrequired to move the bridge plate and associated locking mechanisms froma substantially vertical position to a substantially horizontalposition. The relatively few working parts of the counterbalance deviceare disposed out of the path of travel of the lading as it passes fromone car to the other car over the bridge plate during loading andunloading operations, without such placement impairing the efiicient andsmooth operation of the device. Numerous other benefits and advantageswill become apparent upon a consideration of the more prominent objectsachieved and a full description of the present invention.

It is therefore an object of this invention to provide a bridge plateassembly having a new and improved counterbalance device thereon.

It is a further object of this invention to provide a bridge plateassembly in a piggyback lading car having a counterbalance device togreatly reduce the effort required to move the bridge plate assemblyinto and out of service.

It is a still further object of the invention to provide a simplifiedcounterbalance device for bridge plate assemblies on railway vehicles ofthe piggyback lading type, which counterbalance device is easilyinstalled, highly efiicient and of an economical and lightweight design.

It is a still further object of this invention to provide a new andimproved counterbalance device of simplified design particularly adaptedfor use with bridge plates on piggyback type railway vehicles and whichassists in moving the bridge plate between operative and inoperativepositions.

Further and fuller objects will become readily apparent when referenceis made to the accompanying drawings wherein like reference charactersrefer to like parts.

FIG. 1 is a fragmentary perspective view of an end portion of a carhaving a bridge plate locked in the upright position and illustratingthe counterbalance device of the present invention in the extendedposition;

FIG. 2 is a fragmentary enlarged front elevational View of the bridgeplate and end portion of the car of FIG. 1 with the counterbalancedevice of the present invention in the extended position;

FIG. 3 is an enlarged cross sectional view taken generally along thelines 3-3 of FIG. 2;

FIG. 4 is a top plan View of a fragmentary end portion of the railwaycar and bridge plate illustrating the transverse location of thecounterbalance device of the present invention; and

FIG. 5 is an enlarged side elevational view showing the bridge plate andcounterbalance device of the present invention in solid lines when thebridge plate is in the operative position with phantom lines indicatingthe position assumed when the bridge plate is in the inoperative ortransit position.

Referring now to FIG. 1, reference character 10 indicates a railway carhaving an end portion 11 which terminates in the usual end sill 12. Astationary center sill 13 is provided centrally of the car having asliding sill 14 telescopically received therein in a well known manner.

A bridge plate assembly is indicated at 15 being shown fragmentarilyhaving an open web end portion 16 with center plates 17 in the centralregion of the bridge plate 15. A pair of hinge assemblies 18 and 19 areattached to a trim piece 20 covering the raw ends of the open webbing 16for joining the bridge plate to the car 10 for pivoting movementrelative thereto; The counterbalance device of the present invention isindicated generally by the reference character 27 and generally includesa guide member 28 extending between the hinge assembly 19, and a fixedguide means, indicated generally at 29, carried by the end sill 12 ofthe car 10. The specific details of the counterbalance device of thepresent invention will be given hereinafter in connection with FIGS.2-4.

The hinge assembly 18 includes a pair of hinge plates 21 and 22 attachedto the end trim piece 20 carried by the bridge plate 15. The hingeplates 21 and 22 are in spaced relationship and receive a co-operatingfixed hinge bracket 23 therebetween for joining therewith through theuse of suitable hinge pin means which will be specifically describedhereinafter. The hinge assembly 19 is also provided with a pair ofspaced hinge plates 24 and 25 which are in overlapping engagement withopposite sides of a fixed hinge bracket 26. Plates 24 and 25 are ofincreased depth with respect to plates 21 and 22 for reasons to becomeapparent.

Referring now to FIGS. 2-4, the construction of the counterbalancedevice and the means for attaching the same to the bridge plate assembly15 and railway car 10 will be described. The guide member 28 is formedof a generally cylindrical tubular member 30 having a disklike collar 33of greater diameter capping off the upper end thereof, to provide ashoulder for abutment by one end of a spring 44. A rectangular barmember 31 has one end received in a rectangular opening in the centralportion of the collar 33 and welded thereto. The tubular member 30 maybe joined to the collar 33 in a similar fashion.

The upper end of the bar member 31 is provided with a suitabletransverse aperture 34 aligned with co-operating apertures in theenlarged hinge plates 24 and 25 with suitable means such as theconnecting pin 35 joining the plates and bar member 34 for pivotingmovement therebetween. The pin 35 may be equipped with cotter pins 36and 37 in suitable transverse holes at opposite ends to maintain theguide member 28 joined to the bridge plate 15 by retaining the pin 35 inoperative association with the hinge plates 24 and 25 and bar member 31.

The guide means 29 is formed by a backing plate 40 with side reinforcingplates 58 and 59 joined to an angularly disposed bottom portion 41, thelatter being provided with a central aperture 39 slidably receiving thelower end of the guide member 38. A lower collar member 42 is joined onthe tubular member 30 and limits the upward travel of the guide member28 keeping the spring under slight compression at its fully extendedposition. The backing plate 40 and side reinforcing plates 58 and 59 areattached to the end sill 12 through the interposition of a spacer member43 which is joined to the end sill by means of bolts, riveting or thelike.

The compression spring 44 surrounds the guide member 28 being bottomedon its upper end of the enlarged disklike collar 33, with the oppositeend in abutting engagement with the angularly disposed portion 41 of thebracket 40. As relative movement occurs between the guide member 28 andthe guide means 29, the spring is compressed and extended, storing andreleasing energy to assist in movement of the bridge plate 15 in amanner to be more completely described in connection with FIG. 5, when afull description of the operation of the counterbalance device is given.

The bridge plate 15 is provided with a locking means in dicatedgenerally at 45 and including a locking pin 46 carried on the bridgeplate 15 by means of a pair of spaced guide brackets 47 an-d 48. Thelocking pin 46 is provided with a transverse handle portion 49 tofacilitate easy manual movement thereof along the central longitudinalaxis between fixed limits, from a locked position to an unlockedposition. The lower end of the guide pin 46 is received in a pair ofapertures 52 and 53 formed in fixed locking brackets 50 and 51, with thelatter being attached to web portion of the end sill 12 by means ofwelding or the like. The locked position can only occur when the bridgeplate assembly is in the vertical position allowing the guide pin to beslidably received in the apertures 52 and 53 in the locking brackets 50and 51 respectively. Other forms of locking means which will notinterfere with the counterbalance device 27 are equally suitable. If thelocking means for some reason is accidentally unlocked, the lower collar42 on the guide member 28 will engage the guide means 29 to limit theangular travel of the bridge plate 15 towards the lading on the car toprevent contact therewith, while the spring will resist angular travelin the opposite direction.

As seen in FIGS. 1 and 4, a handle 54 (shown fragmentarily) may beprovided along a marginal edge portion of the bridge plate 15 to allowthe manual movement thereof between the vertical or transit position andthe down or operative position shown in FIG. 4. The construction of thehinge assembly 18 is also evident in FIG. 4, illustrating the hingeplates 21 and 22 joined to the fixed hinge bracket 23 by means of ahinge pin 55 having a pair of collar members 56 and 57 welded onopposite ends to prevent lateral displacement of the hinge pin 55. Anidentical connection is provided for the hinge assembly 19 sodescription thereof is not deemed necessary.

In operation, the bridge plate 15 will be moved to the position shown insolid lines in FIG. 5. Vehicles may pass from the end portion 11 of thecar 10 across the bridge plate 15 to an adjacent railway car in order toallow the rapid loading and unloading of the lading. During thetransportation of the lading or the empty car, the bridge plate is inthe position shown in phantom lines in FIG. 5 with the locking pin 46disposed within the locking brackets 50 and 51 in the manner bestillustrated in FIG. 2. Upon arrival at the destination, the bridge platemay be lowered by pulling upwardly on the handle 49 to withdraw thelocking pin 46, unlocking the bridge plate and allowing it to besubsequently lowered by slight manual effort. With the bridge plate 15in the transit or upright position, the center of mass is practically invertical alignment with the hinge pins 55 connecting the bridge plate 15to the end sill 12. Thus, the hinge assemblies 18 and 19 will carrysubstantially all of the weight of the bridge plate 15. As the bridgeplate 15 is swung about the hinge assemblies 18 and 19 toward theextended position, the center of mass will move in a generally arcuatepath with the horizontal distance between the pin 35 and the center ofmass increasing. Less and less downward weight or force will bedistributed on the hinge pins 55 since the greater portion, actingthrough a lever arm of increasing length will be transferred through thepin 35 to the guide member 28 with the hinge pins on the bridge plate 15ultimately acting as a fulcrum. This causes the guide member to moverelative to the guide means 27 placing the spring 44 in compression dueto the action of the collar 33 on one end, and the resistance of thebottom plate 41 on the other end to movement of the spring 44. In thelowered position of the bridge plate 15, shown in solid lines in FIG. 5,the spring 44 is in the fully compressed position, having maximumpotential energy available to assist in moving the bridge plate 15 tothe upright position.

The value of the potential energy is easily determined by multiplyingthe spring constant times the squared value of the dilferential distancebetween its extended and compressed position, with the total productbeing divided by two, with the qualification that the total deformationremains within the elastic limits of the spring. Accordingly, withchanges in weight of bridge plates, a spring having the appropriateconstant may be provided to develop maximum potential energy, whilepermitting the bridge to remain extended (horizontal).

As the bridge is raised to the transit position the distance of thecenter of mass to the pin 35 decreases in a gradual manner somewhatanalogous to the diminution of force exerted by the counterbalancedevice on the bridge plate. The upward force exerted by the spring 44 isdecreasing, however the lever arm between the hinge 55 (measuredhorizontally) increases reaching a maximum when the bridge plate is atabout a 45 angle. This is made possible by connecting the guide memberabove, and outwardly of the hinge pin 55 when the bridge plate is in avertical position. As the bridge plate swings to a horizontal position,the spring is loaded with the rear edge of hinge plates abutting the endsill to form a stop, at which time the counterbalance is loaded bycompressing the spring 44. The bridge plate may be raised in the mannerdescribed above. Thus, only a light lifting force on the handle 54 isrequired to move the bridge plate 15 upwardly since the spring member 44will assist in the movement until it arrives at the locking positionshown in phantom.

The counterbalance device prevents bridge plates from being dropped dueto the resisting action of the spring, and accordingly reduces thedamage to the ends thereof. It is obvious that short bridge plates coulduse the present invention as well as the long bridge plates shown.

It will become immediately obvious to those skilled in the art thatcertain modifications and variations of the invention may be madewithout departing from the spirit and scope thereof, and therefore onlysuch limitations should be imposed as are indicated in the appendedclaims.

I claim:

1. A railway car having an end sill portion, a bridge plate, hinge meansfixed on said end sill and mounting said bridge plate for angularmovement between a substantially vertical transit position and agenerally horizontal loading position extending outwardly from said endsill, a counterbalance device for assisting in manual movement of saidbridge plate from said horizontal loading position to said verticaltransit position, said counterbalance device including a guide member,means pivotably attaching one end of said guide member to said bridgeplate located at a point outwardly of and eccentric with respect to saidhinge means, guide means mounted on said end sill portion outwardlythereof and below said hinge means and slidably receiving said guidemember for reci rocating movement in a generally vertical direction, ahelical spring surrounding said guide member, said spring having one endthereof movable with said guide member and the other end thereofbottomed on said guide means so as to be compressed upon angularmovement from said vertical transit position to said horizontal loadingposition whereby the total force generated by said spring will increaseas said bridge plate is moved from said substantially vertical transitposition to said substantially horizontal loading position.

2. The railway car of claim 1 wherein a collar is provided on the lowerend of said guide member to limit the upward travel thereof through saidguide means and so that said bridge plate is restrained against angularturning inwardly of said end sill when in said vertical transitposition.

3. In a railway car having a longitudinally movable sill extendingtherefrom and a stationary center sill telescopically receiving saidmovable sill, a bridge plate assembly, hinge means mounting said bridgeplate assembly on said end sill for angular movement between a generallyvertical transit position and a generally horizontal loading positionand extending outwardly from said end sill, a counterbalance devicehaving a guiding portion mounted beneath an end sill portion of said carclosely adjacent said stationary sill, a guide member received in saidguide portion for reciprocating movement outwardly of an end sillportion of said car, said guide member having one end thereof pivotallyattached to said bridge plate eccentric with respect to the axis of saidhinge means, first and second collars on said guide member, one of saidcollars being on one side of said guiding portion with the other collaron the opposite side of said guiding portion, a helical spring meansdisposed about said guide member having one end abutting one of saidcollars with the other end being in abutment with said guiding portion,said spring having a spring constant value with respect to the Weightand length of said bridge plate to permit said bridge plate to remain ina horizontal position when moved thereto While exerting suflicientupward force on said bridge plate to assist in movement thereof to avertical position and which force is of gradually diminishing value assaid bridge plate approaches said vertical transit position.

4. The railway car of claim 3 wherein the one of said collars notengaged by said spring serves to limit the angular movement of saidbridge plate in the direction urged by said spring.

References Cited by the Examiner UNITED STATES PATENTS 933,070 9/09Gleason 114201 1,089,367 3/14 Schroyer -434 2,200,219 5/40 Reid 21342,632,573 3/53 Meyer 213-4 3,063,386 11/62 Price 105458 FOREIGN PATENTS645,237 10/50 Great Britain.

692,147 5/53 Great Britain.

ARTHUR L. LA POINT, Primary Examiner.

LEO QUACKENBUSH, MILTON BUCHLER,

Examiners.

1. A RAILWAY CAR HAVING AN END SILL PORTION, A BRIDGE PLATE, HINGE MEANSFIXED ON SAID END SILL AND MOUNTING SAID BRIDGE PLATE FOR ANGULARMOVEMENT BETWEEN A SUBSTANTIALLY VERTICAL TRANSIT POSITION AND AGENERALLY HORIZONTAL LOADING POSITION EXTENDING OUTWARDLY FROM SAID ENDSILL, A COUNTERBALANCE DEVICE FOR ASSISTING IN MANUAL MOVEMENT OF SAIDBRIDGE PLATE FROM SAID HORIZONTAL LOADING POSITION TO SAID VERTICALTRANSIT POSITION, SAID COUNTERBALANCE DEVICE INCLUDING A GUIDE MEMBER,MEANS PIVOTABLY ATTACHING ONE END OF SAID GUIDE MEMBER TO SAID BRIDGEPLATE LOCATED AT A POINT OUTWARDLY OF AND ECCENTRIC WITH RESPECT TO SAIDHINGED MEANS, GUIDE MEANS MOUNTED ON SAID END SILL PORTION OUTWARDLYTHEREOF AND BELOW AND HINGE MEANS AND SLIDABLY RECEIVING SAID GUIDEMEMBER FOR RECIPROCATING MOVEMENT IN A GENERALLY VERTICAL DIRECTION, AHELICAL SPRING SURROUNDING SAID GUIDE MEMBER, SAID SPRING HAVING ONE ENDTHEREOF MOVABLE WITH SAID GUIDE MEMBER AND THE OTHER END THEREOFBOTTOMED ON SAID GUIDE MEANS SO AS TO BE COMPRESSED UPON ANGULARMOVEMENT FROM SAID VERTICAL TRANSIT POSITION TO SAID HORIZONTAL LOADINGPOSITION WHEREBY THE TOTAL FORCE GENERATED KBY SAID SPRING WILL INCREASEAS SAID BRIDGE PLATE IS MOVED FROM SAID SUBSTANTIALLY VERTICAL TRANSITPOSITION TO SAID SUBSTANTIALLY HORIZONTAL LOADING POSITION.